This invention relates generally to the ink-jet printing art for ejecting ink droplets on the recording medium, such as paper and more particularly, to an ink tank cartridge for use in an ink-jet type recording apparatus such as a printer.
In a conventional recording apparatus, ink is supplied to a recording head from an ink tank constructed as a cartridge. A benefit of using an ink cartridge serving as an ink tank is that ink does not smear due to the leakage of ink while refilling new ink or the like. Controlling the flow of ink from the cartridge is a concern. When ink is supplied from an ink tank, ink in the tank located in a region remote from the supply port flows toward the supply port as a result of a pressure difference. Capillary action of the ink impregnated member or foam in the vicinity of the supply port is increased due to ink consumption.
A cartridge can be divided into multiple chambers, where a porous foam or material is positioned over an outlet port in one chamber and free ink is filled into the other chamber. The free ink migrates from its chamber into the foam through an opening between the two chambers. The foam, in turn, controls the flow of ink that enters an ink outlet port.
If the ink level in the free-ink chamber becomes too high, then the back pressure of ink results in an undesirable excessive flow of ink through the outlet port.
Accordingly, it is desirable to develop a new and improved ink cartridge that meets the above stated needs and others and provides better, more advantageous overall results.
Generally speaking, in accordance with the invention, an ink tank cartridge for an ink-jet type recording apparatus is removably mounted on an ink supply needle of a recording body.
More particularly, the invention relates to an ink tank cartridge having a housing with a divider wall used to separate the housing into first and second chambers. The divider wall has an opening which allows ink to pass between the first and second chambers. An ink supply port with an opening extends through a bottom wall of the housing. A porous member is accommodated in one of the chambers and abuts the opening in the ink supply port. The other chamber is partially filled with ink to a predetermined level. The predetermined level is approximately 2 millimeters above the opening in the bottom wall. This level is used to establish a desired pressure head that prevents excessive flow of ink through the opening in the bottom wall.
A groove is formed in the bottom wall to direct and transfer ink from the porous member to the ink supply port. A filter is positioned between ink supply port and the porous member. The filter is preferably sealed over the grooves in the ink supply port. The porous member has pores of larger size than the pores in the filter.
Still other aspects of the invention will become apparent to those skilled in the art upon reading and understanding the following detailed description.